Closed condylocephalic nailing of peritrochanteric fractures have been utilized with relatively great success (as compared with open hip nailing procedures). The closed condylocephalic nailing procedure was first introduced by Kuntscher in 1966. Kuntscher's method consists of the passage of a curved hollow nail with a clover leaf cross-section over a guide pin from the medial femoral condyle into the medullary canal. The nail is driven retrograde across the fracture site into the femoral head. A flat pin is placed through the distal aspect of the nail to theoretically prevent distal migration. An image intensifier and fracture table are required.sup.1. FNT .sup.1 Kuntscher, G.: A New Method of Treatment of Peritrochanteric Fractures, Proc. Roy. Soc. Med., 63:1120-1121, November 1970.
In 1970 Ender reported a similar technique. Three to four 4.5 millimeter flexible pins are inserted above the medial epicondyle into the medullary canal. Ideally the pins are made to diverge in the femoral head.sup.2. FNT .sup.2 Kuderna, H. Bohler, N., and Collon, D.: Treatment of Intertrochanteric and Subtrochanteric Fractures of the Hip by the Ender Method. J. Bone and Joint Surg. 58-A:604-611 July 1976.
Complications with Kuntscher's and Ender's techniques include penetration of the nail(s) through the femoral head, migration of the nail(s) distally interfering with knee function, and a high incidence of external rotation deformities. An accurate estimation of nail length is critically important in both procedures.
The Kuntscher nail is relatively rigid and designed with a slight curvature as seen in the anterior-posterior (AP) view of FIG. 1 of the drawings, but is planar as viewed laterally or medially (FIG. 2). Its resultant position in the AP view is most often at the superior-lateral cortex of the neck and head; a comparatively weak area for fixation. Therefore, immediate weight bearing is not recommended in unstable fractures.
The Ender pins are designed with a curvature similar to Kuntscher's nail but are much more flexible. Because of the flexibility of the Ender pins, trochanteric osteotomy, through an incision over the hip, is recommended in many stable intertrochanteric fractures. In addition, unstable fractures require additional accessory pins inserted from the lateral femoral condyle. A major complication of this technique is fixation of the fracture in external rotation (noted in 45% of the patients in a recent series using Ender's technique.sup.3.) FNT .sup.3 See footnote 2.
In view of the foregoing, it is desired to redesign a nail for peritrochanteric fractures using a closed condylocephalic operative technique which would offer the following advantages over the prior art:
(a) the nail should be designed with curvature such that it may be consistently placed in an optimal position in the head-neck fragment of the femur; PA1 (b) there should be minimal danger of nail penetration through the femoral head; PA1 (c) the nail should obviate fixation in rotatory malalignment; and PA1 (d) the nail design should provide a margin of error with respect to the selection of the length of nail to be used.
The condylocephalic nail of this invention has been designed to attain the foregoing objectives. Other advantages resulting from the condylocephalic nail of this invention will become apparent from the summary and detailed description set forth hereafter.